Quote:
Originally Posted by fkshiu
Thanks Chin. I knew you couldn't get something for nothing.
Do you know approximately how much bulb life is shortened on an HQI ballast vs. a standard magnetic or electronic one?
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I'm not 100% sure and there are different theories out there but no scientific study have been made (that i'm aware of) to test this. I suspect the lack of testing is primarily due to the fact that deterioration of the bulbs will vary with each of the manufacturers. Having said that, the HQI increases the watts power by about 20-25% and I will be changing mine that much sooner. Instead of changing it every 12-18 months, I will change them at the 12 month mark.
Quote:
Originally Posted by Bryan
Just because a ballast is HQI does not mean it has any additional power advantage. Most cases the double ended bulbs require a HQI ballast is because of the startup characteristics of the ballast.
http://www.fortunecity.com/meltingpo...ie/38/id33.htm
quote:
Most European MH lamps require the use of an ignitor. Standard North American MH lamps usually do not need or should not be used with ignitors. Using pulse ignition MH lamps on non-ignitor systems could cause premature lamp failure. A standard North American ballast (non-ignitor system) will cause excessive stress on the electrodes. Some pulse ignition lamps may not even light on these ballasts. |
The use of HQI ballast with SE bulbs is an intentional decision by the users to overdrive their bulbs. If you go through the spectral plots on Sanjay's site, there is undisputable evidence that the PAR levels are substantially increased by the use of HQI bulbs on SE bulbs but at a cost of electrical consumption and prematuring life expectancy of the bulbs.
As stated, HQI ballast on DE bulbs is just a simple requirement.
On the other hand, the use of ignitors on American bulbs is another issue relating to the setup of the MH setups (including the HQI). Most aquarist will not remove nor install an ignitor due to a lack of understanding the electrial wiring in the ballast box. So most aquarist will leave the ignitor in there regardless if the bulbs they are using needs one but in most cases because the ignitor is present, it will light the bulb and make the aquarist happy not knowing that the ignitor is stressing the electrodes with each startup.